Test indicator



Feb. 13, 1923.

C. H. BULL. TEST INDICATOR. ORIGINA'LH'LED MAR. 24, 1920.

SY Ylllll.

Patented Feb. i3, l923.

itil

. Application mee marchar, ieee, eel-iai yNofeeeaoi'. Renewed iamiaiye, ieee.

useful,Improvements in Test Indicators, oliu which the following` is awspeciication.

rrl`his .inventionrelates to test indicators of `the type employed by 'macliiiiists or others, for the purpose oliquicidy and easily effecting lrefinements Ain measurements ,incidentate ,.inetal viiiacliining` and otherA analo-A gous operations, the primary object of the invention beingy 4to provide `a compact, inechanically correct and reliable instriiment .wherein,features olf construction are provided which, render the instruiiientcapable of regist erin. ;y measurements as line as l/l0,00 O of an inch or other desired miilj tiples thereof.

i. The inventionconsistslesseiitially in 'the prQYisionot a portable Itest indicator wherein `is provided aA dial hodyiipon which mounted, a pivoted armor leyerwhose fiilcruin is so arranged that but relatively slight movement on the -part oithe actuatingend thereof will be sul'licient to create a much larger movement ot its motion transmittiiig` end, said latter end being;` formed, preterably, with gear yteetl'i capable of meshing witlji a movement amplifying gear train olf peculiarA arrangeine-nt, 4the construction be` ing suoli thatthroiigjh the agency oli the fiilcrumeddarin and the cooperative gear Vcon-l struction, the inoveii'ient of the indicator hand of `the device over a calibrated dial Will be sufficient to visually andclearly note the exceedingly minute deflections on thejpart of the operatingend ot said arm.

IThe invention. `further consists in constructing the actuating lmechanism ot the.

indicator insuch manner that when the opits fullest extent from its normal position the indicator hand will be completely rotated several times so that` the range et measurement'ony tliepart of the indicator will be materially increased,` and to provide means in combination with the auctiiatiiipfd mechanism for enabling an operator to dei `note the number of revolutions on the part oit' the indicator hand for eachjgivenloper( tion, this construction being particularly desirable liii that when the actuating mech# anisni is quickly I operated, the indicator hand will rotate with such speed that its` jbodiment ot the invention eratinearm or lever hasbeen oscillated to shown, the tace of the ri `movement can not be readily detected hy the eye, therefore through the provision of the deflection ot' the indicator hand'ffromfits y normal or zero position.

Another object oic the Vinvention resides in" equipping the operating shaft or an equivalent part of `the revolution denoting' means mechanism beingl such `that said structure stresses imparted lto said inechanisnr lliththese and other objects in view, as

will appear as the des criptionV proceeds,the

invention j'r'urtlier consists iii the nove] features ot construction, combinations "of ele? with a spiral or hair spring structure, which'i l lis so arranged as return the actuatingW mechanism and the indicatoihand to noiv mal positions.` the position of the spi'i "e l `striicture with relation tothe actuatiii `will be prete/ted 'from the. `strains and ments and arraiiggeiiient oit parts, toheli'ere f thereof pointed out in the lint the accornpanyiim,l drawing', formi `a part ol the specilication, andYA in which l matter fully describedand to have the scope appended claims."

Figure l is trent elevation oli the ytest inilicatoif compri e" the presentV invention,

Figure 2 is a sectional view ta'lien through the indicator on the liiie`2"2ot Figure' l.

lliguiev is a longitiulinal sectional View' taken through the indicator and illustratiiigj` more i,iarticiilarly the actuating mechanism thereof, and

Figijiire 4a transverse sectional ViewI taken through the indicator on the line ot Figure 2.

Referring more particularly to the ein? af disclosed in the drawing. the numeral l designate my improved indiciator in its entirety.` lis shown, the latter consists ot asiiitabl."

'formed body 2. which p'r lf'erablv' 'oit nu tallii, Li'instriiction and comprises a ico base ii'ftion and a toi-ward etensioiia. The outer `iii this instruire.

trice oi3 the base portion which is secured equipped with a dial ri to the baseV iiortiou in 'any suitable iiiiiniieii4 vfor example byv ineens oi vs ii. is

tal ily Calif construction is covered by means of a crystal 8, which is secured in position by means of a removable annulus 9, the latter being threaded as at 10 to the outer wall of the ring 5. Obviously, through the provision of the crystal 8 the hand 7 will be protected from the effects of the rough usage incident to actual use.

To effect the rotation of the hand 7, use is made of an actuating mechanism which is formed to include a pivoted operating lever or arm 11. This member is So disposed as to extend parallel the longitudinal width of the rear face of the body 2. 1n this instance, the forward end of the lever 11 is arranged to be firmly received by a driving lit between a pair of bifurcated arms 12 provided upon an actuating member 13, the relation between the forward end of the lever 11 and the niember 13 being such that the niovenientof one i will impart corresponding and similar movement to the other, or in other words the parts 11 and 13 are in effect one part. As shown, the arms 12 and the outer end of the lever or arm 11 are provided with registering openings in which a common bushing 111 -is positioned, and a screw 15 rigidly carried by the outer end of the extension L1 is arranged to be positioned within said bushing and to constitute a fulcrum for the operating lever. By the provision of the bushing 14, undue wear upon the screw 15 is eliminated and hence the oscillation of the lever 11 is rendered true and accurate. The outer end of the member 123 is reduced andthreaded as at 16 for the reception of an adjustable case A hardened ball element 17,` which is so positioned as to engage the work upon which the indicator is used, and in thismanner to effect the oscillation of the actuating lever. By rendering the element 17 adjustable slight irregularities in proportion between the actuating mechanism and the indicator hand 7 may be compensated for, inasmuch as the. adjustment of the element 17 will partially regulate the extent of movement of the motion transmitting portion 18 ofthe lever.

Manifestly, owing toftheposition of the fulcrum 15 with respect to the length of the le-` ver 11, relatively slight movement on the part of the actuating end 18 will be sufficient to impart considerably amplied movement to the motion imparting end 18.

To further amplify this movement and to transmit the same to the hand 7 the portion or end 1i tri of the lever 11 is provided with` segmental gear teeth 19. These teeth are so disposed as to mesh with a pinion 2O which is fixed to an idler shaft 21, the latter liaving its ends journaled in the body 2 and also ina bracket 22 carried by the rear face of said body. The teeth of the segment 19 and those of the pinion 20 bear suclrnumerical relation that when the lever 11 has been fully oscillated for any given operation, the

shaft 21 will be caused to effect substantially a complete revolution.` r1`he inner end of the shaft 21 carries a large idler gear 23 which meshes with a reduced pinion 24 fixed to the operating shaft 25 of the hand 7 and it'will be observed that the'teeth of the pinion 241 are approximately,one-fourth the number of those found'upon the. gear 23. Therefore, it follows that when the lever 11 has been fully oscillated `in a given direction the idler shaft 21 will be caused to effect a complete revolution and will thereby impart its motion to the gear 23, the latter, in turn, being substantially four times the size of the pinion 24, will cause the latter to effect substantially four complete revolutions around the dial face 5 upon complete oscillation on the part of the actuating lever. 1n other words, when fully rotated the hand 7 will be capable of registering deflections on the part of the actuating end 13 from its normal position of, in this instance, 320/10,000 of an inch, or when slightly rotated said Vhand will be capable of registering 1/ 10,000 part ofan inch.

1t will thus be manifest that the indicator comprising the present s invention is fully capable of registering very fine and minute measurements and provides a tool for greatly facilitating and promoting fine and indicator but consists in improving such indicators so that the same may be employed to effect much finer readings. Many commercial indicators having a capacityfor per mitting of the registering of 1/1,000 part of an inch, but none to the best of my knowledge have been successfully perfected, prior to the introduction of the present invention, to permit of the registration of v1/1,0,0O0 part of an inch. The general construction of the indicator 1 is such' as to render the same light, compact and portable and to be capable of being easily manipulated so as to be adapted to the requirements of the work` at hand. Another feature is the location of the dial structure, which is positioned to the frontof the indicator, andhence is readily capable of being viewed by the operator at all times during its use and without causing the operatorto assume awkward positions to obtain a view of its readings.v

@wing to the construction of the lever 11 and the associated 'gear train, it will be manifest that slight movements on the part of the end 13 when suddenly or quickly applied will cause the hand 7'to quickly rotate; 1n fact, this motion is so rapid that it is practically impossible for the eye to detect or follow the Same. lt is only when the end 13 is very slowly and carefully moved from its normal position that the movements of the hand 7 may be watched. From this, it will be apparent that unless the operator uses extreme caution he will not know whether or not the hand 7 has completed one or more revolutions.y and in past devices this fact has caused the operator to repeatedly effect measuring operations in order to be positively informed as to the extent of deflection of the hand 7 from its 'normal or Zero position. Therefore, the present invention includes the provision of hand revolution denoting mechanism 26 which is cooperative with the hand 7 to disclose the true position which thelatter may occupy in deflection from its normal position. To this end, use is made of a second idlerv shaft 2T which is positioned in `parallelism with the shaft 25 and-is provided with a fixed gear 28, the lat4 ter being disposed to mesh with the teeth of the pinion 24 formed upon the hand shaft. The gear reduction between the pinion 24 and the gear 28 is such that the idler shaft will effect one complete revolution upon every four complete revolutions of the hand shaft. Therefore, by providing the upper end of the shaft 27 with an indicating finger 29, which is movable over a small registering dial 30, the number of rotations on the part of the hand 7 may be instantly and reliably ascertained by reference to the finger 9 and denoting the position of the latter upon its dial. The provision of the revolution denoting mechanism 26 furnishes, it is believed, one of the major features of the present invention and is believed to constitute a distinct improvement in the art. lts inclusion greatly facilitates indicator readings and eliminates the necessity of repeated adjustments hitherto necessary to denote the positions of an indicator hand which the latter may assume in deflect-ion from its normal position.

. Another important feature of the present invention resides in equipping the shaftl 27 with a hair or spiral spring 3l, one end of said spring being secured to the shaft 27, or an equivalent element, while the opposite end thereof is suitably and rigidly connected with the indicator body. lt will be manifest that the normal tendency exercised by the spring 3l will be to return the actuating mechanism of the indicator, and consequently the hand '7, to normal positions and in this respect the same operates after the fashion of similar devices of the prior art. However, the important factor entering into the use of the spring` 251 is the position which the latter assumes in the indicator. lt will be noted that said spring is employed in conjunction with the idler shaft 2'? and hence even when the hand shaft Q5 has been rotated four complete revolutions, the tension upon the spring 3l will only be increased to an amount equivalent to but one complete revolution on the part of the idler shaft 2T, and therefore the operative condition of the spring 3l will be maintained even after considerable periods of usage. l "'iii'tliei1no1'e, the same will not be subjected to such strains that are incident to undue shocks and blows which may be imparted to the operating end of the lever ll, Past structures usually apply the ,spring directly to the operating lov receive fully whatever jolts and jars are iniparted to a co-operative lever, ln the present invention the spring is securely protected, and the same is only called upon to function strongly when the operating lever has been moved to its greatest extent.

The gear train of the actuating mechanism is preferably located within adjoining circular recesses formed in the rear face of the indicator body, and the arrangement of the different gears comprising the train is suc-h as to insure compactness and yet to maint-ain the desired amplification of movement. A shelf 32 is suitably fixed to the body and is arranged to act as a support for the rear ends of the shafts 25 and 27. It will be noted that the operating lever or arm ll is positioned between a pair of rearwardly project-ing ribs 33 integrally formed with the body 2. These ribs are spaced apart a. distance which will regulate the throw of the motion imparting end of the lever il, and hence the movement of the actuating mechanism as a whole will be regulated and arrested by the contacting of the portion 18 with the inner surfaces of the ribs 33. rlhis feature serves to regulate the extent of movement of the indicating hand 7 and also acts to safeguard the spring 31, in that by arresting the movement of the actuating lever, said spring will be prevented from being wound too tautly. The ribs 33 also carry a sliding cover plate 34, see Figure 4L, from which projects a rigid threaded stud 35, the latter being employed to mount the indicator in its operative position and to permit the same to be readily associated with the work at hand.

vWhile the foregoing description specifically sets forth what is now believed to be the best mode of applying the principles of the invention, yet it should be understood that the description does not necessarily measure the invention except as the latter is defined in the following claims.

What is claimed is:

l. A test indicator comprising a body having a dial face formed therewith, an indicator hand movable over said dial face, an operating lever pivoted at one end to said body, segmental gear teeth provided upon one end of said lever, an idler pinion in mesh with said gear teeth, an idler gear rors thereof, thereby causing the spring to tatable with said pinion, a shaft upon which said indicator hand is mounted, a second pinion fixed to said shaft and in mesh with said idler gear, said gearing serving to amplify the hand rotating motion of said lever, a countershaft, a revolution denoting hand carried by said countershaft, a gear fixed to said countershaft and in mesh with said hand shaft pinion, and a hair spring cooperative with said countershaft and normallyf serving to return the parts of the indicator to normal positions.

2. In a test indicator, a body, an actuating lever pivotally mounted upon said body, said lever being formed to include a bifuroated actuating end and a rigidly associated motion transmitting portion, a bushing eX- tending through openings formed in the elements of' said lever, a pin carried by said body and about which said bushing rotates, an indicator hand, a gearing between said hand and the motion transmitting portionA of said lever.

3. A. test indicator comprising a body having a dial face formed therewith, an indicator hand rotatable over said dial face, an operating lever pivoted to one end of said body, gear teeth provided upon one end of said lever, an idler pinion in mesh With said gear teeth, an idler gear rotatable with said pinion, a shaft upon which said indicator hand is mounted, a second pinion fixed to CLINTON H. BULL. 

